Alert archive / Arizona / Flash Flood Watches in 2021

Flash Flood Watch 10, NWS Las Vegas, NV

August 30, 2021Mohave County, Arizona; San Bernardino County, California; Clark County, Nevada

NWS Las Vegas, NV issued this flash flood watch at Aug 30, 2021, 3:28 AM MST for Mohave County, Arizona; San Bernardino County, California; Clark County, Nevada. It took effect at Aug 31, 2021, 11:00 AM MST. It was in force for 27 hr.

The area

The counties it named.

The facts

Issued
Aug 30, 2021, 3:28 AM MST (10:28 UTC)
In effect from
Aug 31, 2021, 11:00 AM MST
Expired
Sep 1, 2021, 2:11 PM MST
In force
27 hr
Issued by
NWS Las Vegas, NV
Flood severity
None

Counties Mohave County, AZ, San Bernardino County, CA, Clark County, NV

The radar

The Las Vegas radar (KESX), 15 km from the middle of the area, began a volume at 10:31 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Las Vegas, NV (KVEF), launched 00:00Z, 10.5 hours before the alert went out and 101 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Las Vegas, NV at 00:00Z on 2021-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 421 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Las Vegas, NV at 00:00Z on 2021-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -15 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
421 J/kg
Mixed-layer CIN
-6 J/kg
Mixed-layer LCL
3881 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
-15 m²/s²
0-3 km storm-relative helicity
71 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

661 
WGUS65 KVEF 301028
FFAVEF

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Las Vegas NV
328 AM PDT Mon Aug 30 2021

CAZ525-526-301830-
/O.NEW.KVEF.FF.A.0010.210831T1800Z-210901T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morongo Basin-Cadiz Basin-
328 AM PDT Mon Aug 30 2021

...FLASH FLOOD WATCH IN EFFECT FROM TUESDAY MORNING THROUGH LATE
TUESDAY NIGHT...

The National Weather Service in Las Vegas has issued a

* Flash Flood Watch for a portion of southeast California, 
  including the following areas, Cadiz Basin and Morongo Basin. 

* From Tuesday morning through late Tuesday night

* An upper level disturbance coupled with remnant tropical
  moisture from Nora will create conditions favorable for 
  efficient rain producing thunderstorms. Storms that develop in 
  this environment will be capable of producing very heavy rain in
  a short period of time which could result in life threatening 
  flash flooding.

* Areas of concern include Highway 62 east of Yucca Valley to 
  Vidal Junction across the southern portion of San Bernardino 
  County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may become favorable
for flooding of washes...streams and other drainage areas in the
watch area. If you are in the watch area...you should closely
monitor weather forecasts and be prepared to take immediate
action should heavy rain and flooding occur or a flash flood
warning is issued.

Listen to NOAA weather radio...commercial radio or television
stations for updates on this flash flood threat or by visiting us
online at

weather.gov/lasvegas

&&

$$

AZZ002-003-036-CAZ527-NVZ021-301830-
/O.NEW.KVEF.FF.A.0010.210831T1800Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lake Havasu and Fort Mohave-Northwest Deserts-
Lake Mead National Recreation Area-San Bernardino County-
Upper Colorado River Valley-
328 AM PDT Mon Aug 30 2021 /328 AM MST Mon Aug 30 2021/

...FLASH FLOOD WATCH IN EFFECT FROM TUESDAY MORNING THROUGH LATE
WEDNESDAY NIGHT...

The National Weather Service in Las Vegas has issued a

* Flash Flood Watch for portions of northwest Arizona, southeast 
  California, and southern Nevada, including the following 
  areas, in northwest Arizona, Lake Havasu and Fort Mohave, Lake 
  Mead National Recreation Area, and Northwest Deserts. In 
  southeast California, San Bernardino County-Upper Colorado 
  River Valley. In southern Nevada, Lake Mead National 
  Recreation Area. 

* From Tuesday morning through late Wednesday night

* An upper level disturbance coupled with remnant tropical
  moisture from Nora will create conditions favorable for 
  numerous to widespread efficient rain producing thunderstorms. 
  Storms that develop in this environment will be capable of 
  producing very heavy rain in a short period of time which could 
  result in life threatening flash flooding.

* Areas of concern include Highway 95 south of Needles, the
  communities of Lake Havasu City, Needles, Laughlin, and Bullhead
  City within the Colorado River Valley, communities and roads
  vunerable to flash flooding throughout central and southern
  Mohave County, and the Flag Fire burn scar.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may become favorable
for flooding of washes...streams and other drainage areas in the
watch area. If you are in the watch area...you should closely
monitor weather forecasts and be prepared to take immediate
action should heavy rain and flooding occur or a flash flood
warning is issued.

Listen to NOAA weather radio...commercial radio or television
stations for updates on this flash flood threat or by visiting us
online at

weather.gov/lasvegas

&&

$$

AZZ001-301830-
/O.NEW.KVEF.FF.A.0010.210901T1500Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northwest Plateau-
328 AM MST Mon Aug 30 2021

...FLASH FLOOD WATCH IN EFFECT FROM WEDNESDAY MORNING THROUGH
LATE WEDNESDAY NIGHT...

The National Weather Service in Las Vegas has issued a

* Flash Flood Watch for a portion of northwest Arizona, 
  including the following area, Northwest Plateau. 

* From Wednesday morning through late Wednesday night

* An upper level disturbance coupled with remnant tropical
  moisture from Nora will create conditions favorable for 
  efficient rain producing thunderstorms. Storms that develop in 
  this environment will be capable of producing very heavy rain in
  a short period of time which could result in life threatening 
  flash flooding.

* Areas of concern for flooding include rural roads around the Mt.
  Trumbell loop, Highway 389, the community of Colorado City
  within the Short Creek Basin, and Pipe Spring National 
  Monument. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may become favorable
for flooding of washes...streams and other drainage areas in the
watch area. If you are in the watch area...you should closely
monitor weather forecasts and be prepared to take immediate
action should heavy rain and flooding occur or a flash flood
warning is issued.

Listen to NOAA weather radio...commercial radio or television
stations for updates on this flash flood threat or by visiting us
online at

weather.gov/lasvegas

&&

$$
6 follow-up statements
502 
WGUS65 KVEF 301814
FFAVEF

Flood Watch
National Weather Service Las Vegas NV
1114 AM PDT Mon Aug 30 2021

CAZ525-526-310600-
/O.CON.KVEF.FF.A.0010.210831T1800Z-210901T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morongo Basin-Cadiz Basin-
1114 AM PDT Mon Aug 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM TUESDAY MORNING
THROUGH LATE TUESDAY NIGHT...

The Flash Flood Watch continues for

* A portion of southeast California, including the following 
  areas, Cadiz Basin and Morongo Basin. 

* From Tuesday morning through late Tuesday night

* An upper level disturbance coupled with remnant tropical 
  moisture from Nora will create conditions favorable for 
  efficient rain producing thunderstorms. Storms that develop in 
  this environment will be capable of producing very heavy rain 
  in a short period of time which could result in life 
  threatening flash flooding. 

* Areas of concern include Highway 62 east of Yucca Valley to 
  Vidal Junction across the southern portion of San Bernardino 
  County. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may become favorable
for flooding of washes...streams and other drainage areas in the
watch area. If you are in the watch area...you should closely
monitor weather forecasts and be prepared to take immediate
action should heavy rain and flooding occur or a flash flood
warning is issued.

Listen to NOAA weather radio...commercial radio or television
stations for updates on this flash flood threat or by visiting us
online at

weather.gov/lasvegas

&&

$$

AZZ002-003-036-CAZ527-NVZ021-310600-
/O.CON.KVEF.FF.A.0010.210831T1800Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lake Havasu and Fort Mohave-Northwest Deserts-
Lake Mead National Recreation Area-San Bernardino County-
Upper Colorado River Valley-
1114 AM PDT Mon Aug 30 2021 /1114 AM MST Mon Aug 30 2021/

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM TUESDAY MORNING
THROUGH LATE WEDNESDAY NIGHT...

The Flash Flood Watch continues for

* Portions of northwest Arizona, southeast California, and 
  southern Nevada, including the following areas, in northwest 
  Arizona, Lake Havasu and Fort Mohave, Lake Mead National 
  Recreation Area, and Northwest Deserts. In southeast 
  California, San Bernardino County-Upper Colorado River Valley. 
  In southern Nevada, Lake Mead National Recreation Area. 

* From Tuesday morning through late Wednesday night

* An upper level disturbance coupled with remnant tropical 
  moisture from Nora will create conditions favorable for 
  numerous to widespread efficient rain producing thunderstorms. 
  Storms that develop in this environment will be capable of 
  producing very heavy rain in a short period of time which 
  could result in life threatening flash flooding. 

* Areas of concern include Highway 95 south of Needles, the 
  communities of Lake Havasu City, Needles, Laughlin, and 
  Bullhead City within the Colorado River Valley, communities 
  and roads vulnerable to flash flooding throughout central and 
  southern Mohave County, and the Flag Fire burn scar. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may become favorable
for flooding of washes...streams and other drainage areas in the
watch area. If you are in the watch area...you should closely
monitor weather forecasts and be prepared to take immediate
action should heavy rain and flooding occur or a flash flood
warning is issued.

Listen to NOAA weather radio...commercial radio or television
stations for updates on this flash flood threat or by visiting us
online at

weather.gov/lasvegas

&&

$$

AZZ001-310600-
/O.CON.KVEF.FF.A.0010.210901T1500Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northwest Plateau-
1114 AM MST Mon Aug 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM WEDNESDAY MORNING
THROUGH LATE WEDNESDAY NIGHT...

The Flash Flood Watch continues for

* A portion of northwest Arizona, including the following area, 
  Northwest Plateau. 

* From Wednesday morning through late Wednesday night

* An upper level disturbance coupled with remnant tropical 
  moisture from Nora will create conditions favorable for 
  efficient rain producing thunderstorms. Storms that develop in 
  this environment will be capable of producing very heavy rain 
  in a short period of time which could result in life 
  threatening flash flooding. 

* Areas of concern for flooding include rural roads around the 
  Mt. Trumbull loop, Highway 389, the community of Colorado City 
  within the Short Creek Basin, and Pipe Spring National 
  Monument. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may become favorable
for flooding of washes...streams and other drainage areas in the
watch area. If you are in the watch area...you should closely
monitor weather forecasts and be prepared to take immediate
action should heavy rain and flooding occur or a flash flood
warning is issued.

Listen to NOAA weather radio...commercial radio or television
stations for updates on this flash flood threat or by visiting us
online at

weather.gov/lasvegas

&&

$$

Morgan
921 
WGUS65 KVEF 310545
FFAVEF

Flood Watch
National Weather Service Las Vegas NV
1045 PM PDT Mon Aug 30 2021

CAZ525-526-312200-
/O.CON.KVEF.FF.A.0010.210831T1800Z-210901T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morongo Basin-Cadiz Basin-
Including the cities of Vidal Junction, Twentynine Palms, Yucca 
Valley, and Morongo Valley
1045 PM PDT Mon Aug 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM TUESDAY MORNING THROUGH 
LATE TUESDAY NIGHT...

The Flash Flood Watch continues for

* A portion of southeast California, including the following areas, 
  Cadiz Basin and Morongo Basin.

* From Tuesday morning through late Tuesday night.

* An upper level disturbance coupled with remnant tropical moisture 
  from Nora will create conditions favorable for efficient rain 
  producing thunderstorms. Storms that develop in this environment 
  will be capable of producing very heavy rain in a short period of 
  time which could result in life threatening flash flooding.

* Areas of concern include Highway 62 east of Yucca Valley to Vidal 
  Junction across the southern portion of San Bernardino County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

$$

AZZ002-003-036-CAZ527-NVZ021-312200-
/O.CON.KVEF.FF.A.0010.210831T1800Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lake Havasu and Fort Mohave-Northwest Deserts-Lake Mead National
Recreation Area-San Bernardino County-Upper Colorado River Valley-
Lake Mead National Recreation Area-
Including the cities of Laughlin, Golden Valley, Lake Havasu City, 
Yucca, Oatman, Bullhead City, Valentine, Topock, Needles, Mohave 
Valley, Hoover Dam, Desert Hills, Kingman, Wikieup, and Dolan Springs
1045 PM MST Mon Aug 30 2021 /1045 PM PDT Mon Aug 30 2021/

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM TUESDAY MORNING THROUGH 
LATE WEDNESDAY NIGHT...

The Flash Flood Watch continues for

* Portions of northwest Arizona, southeast California and southern 
  Nevada, including the following areas, in northwest Arizona, Lake 
  Havasu and Fort Mohave, Lake Mead National Recreation Area and 
  Northwest Deserts. In southeast California, San Bernardino 
  County-Upper Colorado River Valley. In southern Nevada, Lake Mead 
  National Recreation Area.

* From Tuesday morning through late Wednesday night.

* An upper level disturbance coupled with remnant tropical moisture 
  from Nora will create conditions favorable for efficient rain 
  producing thunderstorms. Storms that develop in this environment 
  will be capable of producing very heavy rain in a short period of 
  time which could result in life threatening flash flooding.

* Areas of concern include Highway 95 south of Needles, the 
  communities of Lake Havasu City, Needles, Laughlin, and 
  Bullhead City within the Colorado River Valley, communities 
  and roads vulnerable to flash flooding throughout central and 
  southern Mohave County, and the Flag Fire burn scar. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

A Flash Flood Watch means that conditions may become favorable for 
flooding of Wheeler Wash and areas adjacent to the Flag Burn Area. 
In steep terrain, the rainfall could trigger debris flows and 
rockfalls. Be prepared to take immediate action should rainfall 
trigger flash flooding.

&&

$$

AZZ001-312200-
/O.CON.KVEF.FF.A.0010.210901T1500Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northwest Plateau-
Including the cities of Western Grand Canyon, Mt Trumbull, Colorado 
City, Tuweep, and Pipe Spring National Monument
1045 PM MST Mon Aug 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM WEDNESDAY MORNING 
THROUGH LATE WEDNESDAY NIGHT...

The Flash Flood Watch continues for

* A portion of northwest Arizona, including the following area, 
  Northwest Plateau.

* From Wednesday morning through late Wednesday night.

* An upper level disturbance coupled with remnant tropical moisture 
  from Nora will create conditions favorable for efficient rain 
  producing thunderstorms. Storms that develop in this environment 
  will be capable of producing very heavy rain in a short period of 
  time which could result in life threatening flash flooding.

* Areas of concern for flooding include rural roads around the 
  Mt. Trumbull loop, Highway 389, the community of Colorado City 
  within the Short Creek Basin, and Pipe Spring National 
  Monument. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

$$

BKP
610 
WGUS65 KVEF 310950
FFAVEF

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Las Vegas NV
250 AM PDT Tue Aug 31 2021

CAZ524-311800-
/O.EXA.KVEF.FF.A.0010.210831T1800Z-210901T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Eastern Mojave Desert-
Including the cities of Mountain Pass, Baker, and Mitchell Caverns
250 AM PDT Tue Aug 31 2021

...FLASH FLOOD WATCH IN EFFECT FROM 11 AM PDT THIS MORNING THROUGH 
LATE TONIGHT...

The National Weather Service in Las Vegas has expanded the

* Flash Flood Watch to include a portion of southeast California, 
  including the following area, Eastern Mojave Desert.

* From 11 AM PDT this morning through late tonight.

* An upper level disturbance coupled with remnant tropical moisture 
  from Nora will create conditions favorable for efficient rain 
  producing thunderstorms. Storms that develop in this environment 
  will be capable of producing very heavy rain in a short period of 
  time which could result in life threatening flash flooding.

* Areas of concern include all roadways within the Mojave National 
  Preserve and National Trails Highway.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

$$

NVZ022-311800-
/O.EXA.KVEF.FF.A.0010.210831T1800Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Southern Clark County-
Including the cities of Primm, Cal-Nev-Ari, and Searchlight
250 AM PDT Tue Aug 31 2021

...FLASH FLOOD WATCH IN EFFECT FROM 11 AM PDT THIS MORNING THROUGH 
LATE WEDNESDAY NIGHT...

The National Weather Service in Las Vegas has expanded the

* Flash Flood Watch to include a portion of southern Nevada, 
  including the following area, Southern Clark County.

* From 11 AM PDT this morning through late Wednesday night.

* An upper level disturbance coupled with remnant tropical moisture 
  from Nora will create conditions favorable for efficient rain 
  producing thunderstorms. Storms that develop in this environment 
  will be capable of producing very heavy rain in a short period of 
  time which could result in life threatening flash flooding.

* Areas of concern include Highway 164 and all secondary roads 
  within southern Clark County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

$$

AZZ001-311800-
/O.EXT.KVEF.FF.A.0010.210831T1800Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northwest Plateau-
Including the cities of Western Grand Canyon, Mt Trumbull, Colorado 
City, Tuweep, and Pipe Spring National Monument
250 AM MST Tue Aug 31 2021

...FLASH FLOOD WATCH NOW IN EFFECT FROM 11 AM MST THIS MORNING 
THROUGH LATE WEDNESDAY NIGHT...

The Flash Flood Watch is now in effect for

* A portion of northwest Arizona, including the following area, 
  Northwest Plateau.

* From 11 AM MST this morning through late Wednesday night.

* An upper level disturbance coupled with remnant tropical moisture 
  from Nora will create conditions favorable for efficient rain 
  producing thunderstorms. Storms that develop in this environment 
  will be capable of producing very heavy rain in a short period of 
  time which could result in life threatening flash flooding.

* Areas of concern for flooding include rural roads around the 
  Mt. Trumbull loop, Highway 389, the community of Colorado City 
  within the Short Creek Basin, and Pipe Spring National 
  Monument. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

$$

CAZ525-526-311800-
/O.CON.KVEF.FF.A.0010.210831T1800Z-210901T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morongo Basin-Cadiz Basin-
Including the cities of Vidal Junction, Twentynine Palms, Yucca 
Valley, and Morongo Valley
250 AM PDT Tue Aug 31 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 11 AM PDT THIS MORNING 
THROUGH LATE TONIGHT...

The Flash Flood Watch continues for

* A portion of southeast California, including the following areas, 
  Cadiz Basin and Morongo Basin.

* From 11 AM PDT this morning through late tonight.

* An upper level disturbance coupled with remnant tropical moisture 
  from Nora will create conditions favorable for efficient rain 
  producing thunderstorms. Storms that develop in this environment 
  will be capable of producing very heavy rain in a short period of 
  time which could result in life threatening flash flooding.

* Areas of concern include Highway 62 east of Yucca Valley to Vidal 
  Junction across the southern portion of San Bernardino County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

$$

AZZ002-003-036-CAZ527-NVZ021-311800-
/O.CON.KVEF.FF.A.0010.210831T1800Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lake Havasu and Fort Mohave-Northwest Deserts-Lake Mead National
Recreation Area-San Bernardino County-Upper Colorado River Valley-
Lake Mead National Recreation Area-
Including the cities of Laughlin, Golden Valley, Lake Havasu City, 
Yucca, Oatman, Bullhead City, Valentine, Topock, Needles, Mohave 
Valley, Hoover Dam, Desert Hills, Kingman, Wikieup, and Dolan Springs
250 AM MST Tue Aug 31 2021 /250 AM PDT Tue Aug 31 2021/

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 11 AM MST /11 AM PDT/ 
THIS MORNING THROUGH LATE WEDNESDAY NIGHT...

The Flash Flood Watch continues for

* Portions of northwest Arizona, southeast California and southern 
  Nevada, including the following areas, in northwest Arizona, Lake 
  Havasu and Fort Mohave, Lake Mead National Recreation Area and 
  Northwest Deserts. In southeast California, San Bernardino 
  County-Upper Colorado River Valley. In southern Nevada, Lake Mead 
  National Recreation Area.

* From 11 AM MST /11 AM PDT/ this morning through late Wednesday 
  night.

* An upper level disturbance coupled with remnant tropical moisture 
  from Nora will create conditions favorable for efficient rain 
  producing thunderstorms. Storms that develop in this environment 
  will be capable of producing very heavy rain in a short period of 
  time which could result in life threatening flash flooding.

* Areas of concern include Highway 95 south of Needles, the 
  communities of Lake Havasu City, Needles, Laughlin, and 
  Bullhead City within the Colorado River Valley, communities 
  and roads vulnerable to flash flooding throughout central and 
  southern Mohave County, and the Flag Fire burn scar. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

A Flash Flood Watch means that conditions may become favorable for 
flooding of Wheeler Wash and areas adjacent to the Flag Burn Area. 
In steep terrain, the rainfall could trigger debris flows and 
rockfalls. Be prepared to take immediate action should rainfall 
trigger flash flooding.

&&

$$

BKP
556 
WGUS65 KVEF 311733
FFAVEF

Flood Watch
National Weather Service Las Vegas NV
1033 AM PDT Tue Aug 31 2021

NVZ022-010900-
/O.CON.KVEF.FF.A.0010.210831T1800Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Southern Clark County-
1033 AM PDT Tue Aug 31 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE WEDNESDAY
NIGHT...

The Flash Flood Watch continues for

* A portion of southern Nevada, including the following area, 
  Southern Clark County. 

* Through late Wednesday night

* An upper level disturbance coupled with remnant tropical 
  moisture from Nora will create conditions favorable for 
  efficient rain producing thunderstorms. Storms that develop in 
  this environment will be capable of producing very heavy rain 
  in a short period of time which could result in life 
  threatening flash flooding. 

* Areas of concern include Highway 164 and all secondary roads 
  within southern Clark County. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.

&&

$$

CAZ524>526-010900-
/O.CON.KVEF.FF.A.0010.210831T1800Z-210901T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Eastern Mojave Desert-Morongo Basin-Cadiz Basin-
1033 AM PDT Tue Aug 31 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE TONIGHT...

The Flash Flood Watch continues for

* A portion of southeast California, including the following 
  areas, Cadiz Basin, Eastern Mojave Desert, and Morongo Basin. 

* Through late tonight

* An upper level disturbance coupled with remnant tropical 
  moisture from Nora will create conditions favorable for 
  efficient rain producing thunderstorms. Storms that develop in 
  this environment will be capable of producing very heavy rain 
  in a short period of time which could result in life 
  threatening flash flooding. 

* Areas of concern include Highway 62 east of Yucca Valley to 
  Vidal Junction across the southern portion of San Bernardino 
  County, and roads in the Mojave National Preserve. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.

&&

$$

AZZ001>003-036-CAZ527-NVZ021-010900-
/O.CON.KVEF.FF.A.0010.210831T1800Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northwest Plateau-Lake Havasu and Fort Mohave-Northwest Deserts-
Lake Mead National Recreation Area-San Bernardino County-
Upper Colorado River Valley-
1033 AM PDT Tue Aug 31 2021 /1033 AM MST Tue Aug 31 2021/

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE WEDNESDAY
NIGHT...

The Flash Flood Watch continues for

* Portions of northwest Arizona, southeast California, and 
  southern Nevada, including the following areas, in northwest 
  Arizona, Lake Havasu and Fort Mohave, Lake Mead National 
  Recreation Area, Northwest Deserts, and Northwest Plateau. In 
  southeast California, San Bernardino County-Upper Colorado 
  River Valley. In southern Nevada, Lake Mead National 
  Recreation Area. 

* Through late Wednesday night

* An upper level disturbance coupled with remnant tropical 
  moisture from Nora will create conditions favorable for 
  efficient rain producing thunderstorms. Storms that develop in 
  this environment will be capable of producing very heavy rain 
  in a short period of time which could result in life 
  threatening flash flooding. 

* Areas of concern include Highway 95 south of Needles, the 
  communities of Lake Havasu City, Needles, Laughlin, and 
  Bullhead City within the Colorado River Valley, communities 
  and roads vulnerable to flash flooding throughout central and 
  southern Mohave County, and the Flag Fire burn scar. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.

A Flash Flood Watch means that conditions may become favorable
for flooding of Wheeler Wash and areas adjacent to the Flag Burn
Area. In steep terrain, the rainfall could trigger debris flows
and rockfalls. Be prepared to take immediate action should
rainfall trigger flash flooding.

&&

$$

Morgan
171 
WGUS65 KVEF 010859
FFAVEF

Flood Watch
National Weather Service Las Vegas NV
159 AM PDT Wed Sep 1 2021

NVZ022-011000-
/O.CAN.KVEF.FF.A.0010.000000T0000Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Southern Clark County-
Including the cities of Primm, Cal-Nev-Ari, and Searchlight
159 AM PDT Wed Sep 1 2021

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for a portion of southern Nevada, including 
the following area, Southern Clark County has been cancelled.

The Flash Flood Watch is cancelled. Flooding is no longer expected 
to pose a threat.

$$

CAZ524>526-011000-
/O.EXP.KVEF.FF.A.0010.000000T0000Z-210901T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Eastern Mojave Desert-Morongo Basin-Cadiz Basin-
Including the cities of Mountain Pass, Twentynine Palms, Mitchell 
Caverns, Baker, Morongo Valley, Yucca Valley, and Vidal Junction
159 AM PDT Wed Sep 1 2021

...FLASH FLOOD WATCH WILL EXPIRE AT 2 AM PDT EARLY THIS MORNING...

The Flash Flood Watch for a portion of southeast California, 
including the following areas, Cadiz Basin, Eastern Mojave Desert 
and Morongo Basin will expire at 2 AM PDT early this morning.

Flooding is no longer expected to pose a threat.

$$

AZZ002-003-036-CAZ527-NVZ021-012200-
/O.CON.KVEF.FF.A.0010.000000T0000Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lake Havasu and Fort Mohave-Northwest Deserts-Lake Mead National
Recreation Area-San Bernardino County-Upper Colorado River Valley-
Lake Mead National Recreation Area-
Including the cities of Laughlin, Golden Valley, Lake Havasu City, 
Yucca, Oatman, Bullhead City, Valentine, Topock, Needles, Mohave 
Valley, Hoover Dam, Desert Hills, Kingman, Wikieup, and Dolan Springs
159 AM MST Wed Sep 1 2021 /159 AM PDT Wed Sep 1 2021/

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE TONIGHT...

The Flash Flood Watch continues for

* Portions of northwest Arizona, southeast California and southern 
  Nevada, including the following areas, in northwest Arizona, Lake 
  Havasu and Fort Mohave, Lake Mead National Recreation Area and 
  Northwest Deserts. In southeast California, San Bernardino 
  County-Upper Colorado River Valley. In southern Nevada, Lake Mead 
  National Recreation Area.

* Through late tonight.

* An upper level disturbance coupled with remnant tropical moisture 
  from Nora will create conditions favorable for efficient rain 
  producing thunderstorms. Storms that develop in this environment 
  will be capable of producing very heavy rain in a short period of 
  time which could result in life threatening flash flooding.

* Areas of concern include Highway 95 south of Needles, the 
  communities of Lake Havasu City, Needles, Laughlin, and 
  Bullhead City within the Colorado River Valley, communities 
  and roads vulnerable to flash flooding throughout central and 
  southern Mohave County, and the Flag Fire burn scar. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

A Flash Flood Watch means that conditions may become favorable for 
flooding of Wheeler Wash and areas adjacent to the Flag Burn Area. 
In steep terrain, the rainfall could trigger debris flows and 
rockfalls. Be prepared to take immediate action should rainfall 
trigger flash flooding.

&&

$$

AZZ001-012200-
/O.CON.KVEF.FF.A.0010.000000T0000Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northwest Plateau-
Including the cities of Western Grand Canyon, Mt Trumbull, Colorado 
City, Tuweep, and Pipe Spring National Monument
159 AM MST Wed Sep 1 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE TONIGHT...

The Flash Flood Watch continues for

* A portion of northwest Arizona, including the following area, 
  Northwest Plateau.

* Through late tonight.

* An upper level disturbance coupled with remnant tropical moisture 
  from Nora will create conditions favorable for efficient rain 
  producing thunderstorms. Storms that develop in this environment 
  will be capable of producing very heavy rain in a short period of 
  time which could result in life threatening flash flooding.

* Areas of concern for flooding include rural roads around the 
  Mt. Trumbull loop, Highway 389, the community of Colorado City 
  within the Short Creek Basin, and Pipe Spring National 
  Monument. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

$$

BKP
719 
WGUS65 KVEF 012111
FFAVEF

Flood Watch
National Weather Service Las Vegas NV
211 PM PDT Wed Sep 1 2021

AZZ001>003-036-CAZ527-NVZ021-012215-
/O.CAN.KVEF.FF.A.0010.000000T0000Z-210902T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northwest Plateau-Lake Havasu and Fort Mohave-Northwest Deserts-
Lake Mead National Recreation Area-San Bernardino County-
Upper Colorado River Valley-
211 PM PDT Wed Sep 1 2021 /211 PM MST Wed Sep 1 2021/

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for portions of northwest Arizona,
southeast California, and southern Nevada has been cancelled.

The threat for widespread heavy rain has moved away to the east,
and only spotty showers and thunderstorms are expected over
eastern Mohave County for the rest of the afternoon.

$$

Morgan

The office that day

Everything else NWS Las Vegas, NV issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 29, 5:42 PM MSTSevere Thunderstorm WarningVEFMohave48 min
Aug 30, 4:30 PM MSTFlash Flood Warning Considerable damage threatVEFMohave100 min
Aug 30, 4:35 PM MSTFlash Flood Warning Considerable damage threatVEFMohave3 hr
Aug 29, 6:53 PM MSTFlash Flood Warning Considerable damage threatVEFSan Bernardino3 hr
Aug 30, 1:17 PM MSTFlash Flood Warning Considerable damage threatVEFSan Bernardino3 hr
Aug 30, 2:37 PM MSTFlash Flood Warning Considerable damage threatVEFSan Bernardino3 hr
Aug 30, 2:55 PM MSTFlash Flood Warning Considerable damage threatVEFSan Bernardino3 hr

Nearby

Flash Flood Watches in Arizona, 2021Flash Flood Watches in California, 2021Flash Flood Watches in Nevada, 2021Every flash flood watch in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.